The fabrication of all-printed backplanes on polymeric substrates through use of solvent-based inks offers the potential for lower cost, flexible, or large area displays. There are numerous potential applications for such displays, such as: rolled displays; affordable large area displays; displays incorporated into fabrics; and as a paper substitute. Unfortunately, the solvent in the ink materials will typically attack previously deposited organic layers or a polymer substrate. This attack can lead to damage of an organic layer or its interface with other layers, as through intermixing of layers.
In particular, the interface between an organic semiconductor and a gate dielectric is critical to the performance of a organic-based thin-film transistor (“OTFT”). Solvent used to pattern the semiconductor can damage an organic dielectric, while deposition of an organic dielectric can entail use of a solvent that damages an organic semiconductor. Further, standard cleaning solvents, for example acetone and isopropanol, can affect organic interfaces. Attempts to use materials that are solvent tolerant greatly reduces the choice of materials available for formation of OTFTs.
What are needed are relatively simple, low cost manufacturing methods that reduce solvent caused damage to organic layers to help realize the advantages of OTFTs on polymer substrates.